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Air Flow Meter/Sensor: Testing and Inspection

1. Inspect the mass air flow sensor for damage and cracks.
2. Warm up the engine to normal operating temperature.
3. Shift the selector lever to P.

4. Turn off all electric loads.
- Headlight
- Blower motor
- Rear window defroster
- Power steering

5. Wait until the cooling fan stops.




6. Connect the SSTs to the data link connector-2.




7. Select the PID/DATA MONITOR AND RECORD function of the NGS.
8. Select "MAF V" on the NGS display. NGS measures and shows the voltage.




Specification

9. . If not as specified, perform following inspection.
Harness continuity.
- Between PCM terminal 3E and mass air flow sensor terminal B
- Between PCM terminal 4D and mass air flow sensor terminal A
- Between PCM terminal 4A and mass air flow sensor terminal C

10. If there is incorrect terminal voltage or harness continuity, replace the mass air flow sensor.

NOTE: The scan tool shows the mass air flow rate and load value.




Specification